Evaluation and redesign of manual material handling in a vaccine production centre's warehouse

This study was conducted in a warehouse at a vaccine production centre where improvement to existing storage and working conditions were sought through the construction of a new refrigerated store section (2-8C°). Warehousing tasks were videotaped and ergonomics analysis tools were used to assess the risk of developing MSDs. Specifically, these tools were the Rapid Entire Body Assessment (REBA) and the NIOSH equation. The current plant layout was sketched and analyzed to find possible targets for improvement trough the application of general work space design and ergonomics principles. Seven of the eight postures evaluated with REBA had a total score between 8 and 10, meaning a high risk, and only one was at a medium risk level. Nine of the eleven manual material handling tasks analyzed with the NIOSH equation had a Lifting Index between 1.14 and 1.80 and two had a recommended weight limit of 0 kg, indicating a need for job redesign. Solutions included the redesign of shelves, the design of a two-step stair and a trolley with adjustable height; also, changes in work methods were proposed by introducing a two-workers lifting strategy and job rotation, and, finally, a restructuring of plant layout was completed.